without commenting much on the nature of analog/digital , i just want to lay out my understanding of the word ‘analog’ because it has conflicting meanings im pretty sure (and often i am confused by it):
- the word analog has a technical meaning in electronics to mean a continuous parameter or signal, for example how an analog-to-digital converter reads a continuous voltage signal.
- this use comes from the english word analogy ie to compare two things - in this case the (continuous) signal is comparable to the output. for example a telephone line carries a varying voltage signal which is analogous to the varying pressure of sound-waves in the receiver. a counter point would be a morse-code telegram, where the (discrete) signal is encoded and decoded, not analogous to the message.
- as we know this electrical use of analog also applies to (tube) television , where the varying voltage in a video signal is analogous to the intensity of electron-gun (and thus brightness of the resulting image)
it seems analog has since taken on another different meaning, as a retronym to describe something not digital. my guess is this came from the naming of analog clocks (since the hands do move continuously) to distinguish from digtial clocks. but is now applied (without any connection to the electrical/original meanings):
- analog photography , to now distinguish from digital photography
- analog film, to now distinguish from digital film.
the film part is particularly confusing because analog film creates the illusion of motion by flickering over discrete (chemically exposed) images - much closer to how digital video does, than analog imo. (unless theres another reason why we call chemically processed film analog that i havent heard ?)
maybe we should have started calling it acoustic film to distinguish from electric film instead ?